Electromagnetic relay



Oct. 6, 1936. E STALNAKER 2,056,745

ELECTROMAGNETIC RELAY Filed Jan. 24, 1930 iii/Q1227? 7451 G E/wv STALA/A/f'fi' [KW/155.6 WA, M x

Patented Oct. 6, 1936 UNITED STATES PATENT OFFICE ELncraomGNnrrc RELAY m1 Glenn same, Chicago, 111. Application January 24, 1930, Serial No. 423,104

1' Claim. (curs-s39) mitter for sending periodic impulses, a radio receiving set tuned to receive the impulses transmitted, and a relay operated upon receipt of the impulses directed from the receiving set, the relay,v in turn, operating .the secondary electric clock or other device.

Heretoforefiin so far as applicant is aware, there have been devices which are said to be adapted to be utilized in correcting clocks by Hertzian waves transmitted through space from a central station at which a standard time piece is located. These devices are corrective in func- "tion and do not actually operate the clock.

Applicant contemplates the operation of a secondary clock by impulses sent periodically, preferably by seconds, from a master clock, the operation of the secondary clock being eifected and controlled by a relay susceptible to the slightest electrical impulse but not affected by mechanical vibration or shocks.

One of the objects of this invention is to provide a system for operating a secondary clock or other similarly-actuated mechanism from a transmitting agency through electrical waves.

Another object of this invention is to provide a simple, practical system of the above character for remotely controlling devices through a positively relay.

Other objects andadvantages will hereinafter be more fully pointed out and for a more complete description of the characteristic features of this invention, reference may now be had to the following description and the accompanying drawing, in which latter: I

Theflgureisa-wiringdiagram'of oneform of system of radio control embodyingthe fea tures of this invention.

Referring now to the the system 'mown therein comprises a master clock control,

a radio receiving lmit, a relay and a secondary electric clock, or other devices subject to re- 'mote control such as soundera regisw ters, typewriters, and the like. 7

Referring first to the master clock control, thedevieeshowneomprisesamasterclockof theusualcharactermchastheoneemployed .tthe United States t stationiat Arcontact members 26 and 21 lington, Virginia,-the illustration showing but a fragmentary portion consisting of a small metal block Ilia fastened on the pallet shaft l having the usual pallet points and the pendulum |2 depending therefrom. The block Ina. is grounded B to the frame of the clock and has a pair of horizontally extending arms II and H extending adjustably on opposite sides thereof and depending end portions l3 and I4, respectively, from the horizontally extending portions for dipping into containers l5 and IS, the latter beingdilled substantially with mercury and having a film of oil thereover to prevent deterioration of the mercury. Electrodes l1 and H; extend through the bottom surface of the containers a. substantial distance into the mercury and "have wires l9 and '20 connected respectively to said electrodes and extending therefrom. The wires I9 and lead to a single-pole-doublethrow switch 2|, the single pole thereof being .20 connected to one end of the winding of the re lay 22, the other end of the winding being connected through a battery 23 to the ground 24 of the clock. "The relay 22 has the usual pair of which are bridged 25 by the armature 25 to close the circuit through a radio transmitter. v

In the operation of the device thus far described, when the depending portion iii of the arm dips through the film of oil and into the mercury in the container IS, the circuit is closed through the wire I9 and the single-pole of the double-throw switch 2| to energize the magnet of the relay 22 to attract the armature and thereby make contact with the terminals 26 and 21 whereby the radio transmitter is energized. The secondary clock which is to be controlled has a predetermined beat and, therefore, the pendulum I2 is so regulated to dip. the arm portion I3 into the mercury to energize the radio transmitter and thereby to send impulses at such a predetermined rate.

In case an abnormal condition should exist in the circuit just described, then the pole of the single-double-throw switch'may be operated to the other side of the switch whereby a dip of the depending portion H of the arm into the mercury in the container I6 would energize the circuit through the wire 20 to the switch 2| and thence tothe relay 22 and through the battery tothe ground of the clock frame. However, it may be desirable to have both arms II and l energize their respective circuits whereby the number of impulses sent through the radio transmitter will be doubled since it is usualin secondary clocks to have a 60 beat or 120 beat movement. I

Referring now to the radio receiving set, this, may be of any desired type, although the short We will wave set has been found preferable. hereinafter show and describe a radio receiving set operated by dry cells, although it is to be understood that the radio receiver may be operated through any desirable source of power and that a set such as is commonly known to the trade as an all-electric receiving set may be employed in this connection. The receiver illustrated in the drawing comprises one of a number of well known short wave hook-ups having a wave length coil such as are employed in short wave sets. The antenna 23 picks up the waves transmitted from the radio transmitter just described and sends the impulses through i a lead-in-wire 29 to the terminal of a. variable south pole in substantial axial alignment with coil 33. It will be noted that the face surface 34b of the T-head of the lower core is substantially greater than the face surface 331) of the T-head of the uppercore. Armature 35 is tiltably mounted on the other vertically extending full leg of the core of the magnet and extends between the enlarged face surfaces of the ends of the portions 331; and 34a,'the free end i of the armature being adapted to operate between a terminal 36 and an insulated pin 31, both of the latter. members being adjustable to limit the vertically tiltable movement of the armature 35. One end of the coil 34 is connected with one end of the coil 33, the other end of the coil 33 being connected to the plate side of the tube 39 constituting the last stages .of amplification of the radioreceiving set, and

the other end of the coil34 extending to the plus side of the B battery 38. Terminal 36 is connected to the positive of the A battery, as

shown in the figure.

In the operation of the system thus far described, whenan impulse is received in the radio receiver, an impulse flows from the plus side of the B battery 38 through the lower magnet coil 3!, the upper magnet coil 33 and back to the battery through the elements of the tube 39. When the radio set is in operation and no impulses are received from the .radio transmitter, the electromagnet It therefore is energized whereby the iron circuit is completed by reason of the core portion 331 attracting the armature 35 and holding the same against theterminal 36. This action of the armature closes the circuit therethrough to the frame of the magnet 3|, thence to one terminal ofthe magnet 40 of the secondary clock or other instrument to be controlled, the other side of the magnet oi the secondary clock being connected to the negative side of an A battery, or to any battery or, source of power. It may be desirable to employ a higher voltage for controlling a typewriter or other machine, and this may be conveniently arranged independently of the radio circuit, the connection shown herein being purely illustrative.

The secondary clock illustrated in the drawing is of the type shown and described in Patent No. 1,587,047, patented June 1, 1926 and issued to the applicant of the present application. The clock comprises a frame in which are mounted a series of shafts connected by gearing in the usual manner. When the escapement and the associated weighted beveled armature are dis posed as shown in the drawing, the armature moves from one position to the other to engage the core of the magnet to draw down one of the pallet points'to engage one of the teeth of the escapement wheel thereby causing the wheel to move a predetermined amount. When the electric'impulse ceases the weighted armature -moves the other of the pallet points downwardly to engage a tooth of the escapement wheel to move the same a distance in the same direction,

the same predetermined amount as before described with reference to the other pallet point. The wheel preferably has Bl! teeth and when an oscillatory movement ofthe armature is completed, the wheel will have moved a distance equal to 1/60th of its circumference. course, may be varied at will.

With reference to the operation of the entire system when no impulse is received from the radio transmitter and the receiver is energized, the armature 35 normally occupies a position against the terminal 36 to complete a circuit through the device to be remotely controlled such as the hereinbefore described secondary electric clock. To deenergize this latter circuit, an impulse is received by the receiver and flows from the plus side of the B battery 38 through the lower magnet coil 34, upper magnet coil 33, and back to the battery through the elements of the tube 39, whereby the magnetic attraction of the core portion 33a for the armature 35 is overcome by the core portion 34a and the ar'mature is moved downwardlyout of contact with; terminal 36 against the insulating pin 31.

a The armature 35 is so positioned that, even when resting upon the insulating pin 31, it will be biased toward theupper or north pole limb of the permanent magnet 32, as a result'of which it will naturally attempt to come in contact with the pole face 33b, but will be prevented from so doing by reason of the fact thatthe extreme free .end of the armature 35 will touch the contact 36, thereby closing 7 the circuit through the electromagnet 40. This accomplishes two-very important results: first, accidental jars will not tend to disturb the circuitj and, second, when the impulse is received and. is of sufiicient duration-say one-tenth of a secondthere will be time to overcome the lag of the magnet and insm'e the pulling down of the armature 35 toward the south pole of the magnet. This effect is enhanced by making the terminal of the lower limb of the magnet 3 larger by extending it into the form of a plate 34b. As soon as the impulse received through the ether ceases, the natural magnetism of the magnet will again assert itself, thereby pum the armatm'e 35 upward into contact with the contact pin 35, whereby the current flowing through the coil of the electro-magnet I is This, of

re-established; and as a result thereof, the .armature connected with the pallet of the clock movement i c attractedtowardondcunesm' contact with the core 0! the said electromagnet l.

. it will thus be seen that with each impulse received by the radio receiver there will be an interruption in the secondary circuit, which consists of the battery, the circuit wires, and the electromagnet 40, whereby, under the weight of the armature connected with the pallet, the

said armature will drop and the pallet will actu-' driven by the impulses which are received from the radio transmitter itself. The present device differs from all previously known electric devices for showing time in that it is, positively driven by impulses received at definite intervals oi. time,

while the prior art devices concern themselves merely with periodic adjustments whereby clocks that are either in advance of or behind the true time are brought into synchronism with the mastter clock. The present clock, on the contrary, is at all times in direct accord with the master clock because each impulse, as received and am plified by the circuits hereinabove described,

serves directly to actuate the clock itself. This is an essential and important feature of the present invention.

While but one embodiment of this invention is herein shown and-described, it is to be understood that various modiflcations thereof may be apparent to those skilled in the art without departing from the spirit and scope of this invention and, therefore, the same is only to be limited by the scope oi! the priorart and the appended claim.

Iclaim:

An electromagnetic relay comprising the combination of a G-shaped permanent magnet formed of arms having two opposed pole pieces of opposite polarity at the gap of said magnet, one of said pole pieces being considerably larger than the other, coil windings on the two opposing poles of said magnet, the windings being so arranged that when current is passed through the coils the electromagnetic field set up will be opposed to the polarity 0! one or the arms of the magnet, a movable armature pivotally attached to the magnet body and horizontally disposed between the said poles, and means for biasing said armature toward one of the poles of said magnet.

EARL GLENN STALNAKER. 

